While a large portion of potential problems with old shotguns seem to be caused by recoil, one still needs to be conscious of produced pressures. This holds true for all guns manufactured before or around the time that SAAMI standards were established. Prior to these standards, common pressures ran around 6,000-8,000 psi, and most guns were designed for a steady diet of cartridges in this range. Once these standards were introduced, establishing "acceptable" max pressures, an immediate push towards flirting with those max's ensued. [After all, any good American knows that more is better, when it comes to firepower
.] This rush to acheive the max made several makes and models of shotgun somewhat obsolete. Not that they would blow up or anything, they just weren't designed to take that kind of abuse on a regular basis. [Older Ithaca's are one of those.]
My point here is that while reducing payload, thus recoil, is certainly a good idea with any older gun, don't forget produced pressures. I get nervous any time someone mentions old guns and "high" or "low" brass in the same breath. The height of a cartridge's brass has nothing to do with what pressures it may produce. In fact, it often has little to do with payload. A shotshell relies solely on the chamber walls to keep from blowing up. A solid brass cartridge is no better than one made completely of plastic, without that chamber. The ammo companies know this, and could produce "magnum" loads of solid plastic. That wimpy looking plastic cartridge wouldn't sell well, however. Especially not to those looking to kill those rhino skinned mallards we have here in the U.S.
. The reverse is also true. Brass costs money in production. Clay targets don't have rhino type skins. Lower brass on target loads is, therefore, acceptable. However, we still need those loads to be fast. A 150fps increase in pellet speed means we're getting our payload to the target that much faster. Despite the fact that the difference in lead [time/space] is almost immeasurable, we're certain it makes a difference in score.
Take a fairly light payload, kick up the velocity a notch or two, and you've just increased recoil, and most probably pressure. It still has "low" brass, however.
When shooting any older gun, take pressure as well as recoil into consideration. Light payloads can decrease recoil, but don't always decrease produced pressures. Look for published sources as to the pressures expected from any given load. Many major brands won't give you this information. Ask them anyway. If enough of us ask, they may eventually see the light and give this information freely. Meanwhile, Winchester makes two target loads that produce pressures in the 7,000 psi range,[low noise/low recoil, and X-tra lite target]. There are some other brands, such as RST, Gamebore, and ARMUSA, which produce low pressure loads as well, and freely give this information. You can also load your own low pressure cartridges, there are numerous published recipes.
Sorry for the soapbox speech, but this "high/low brass" rhetoric, in this context, isn't good,[IMO].